Tool-holder



0. GUSTAFSON.

TOOL HOLDER.

APPLICATION FILED MAY 12. 1920.

Patented May 31, 1921.

4 SHEETS-SHEE Patnted May'BI, 1921.

4 swans-SHEET lnbzentar:

Oscar Gugtqjsong by (9 .O. GUSTAFSON.

TOOL HOLDER. APPLICATION FILED MAY I2, 1920.

0. GUSTAFSON. TOOL HOLDER.

APPLICATION FILED MAY I2. 1920- 4 SHEETS-SHEET 3- f fll fiugeniort OscarGmlqfsbn,

0. GU'STAFSON.

TOOL HOLDER.

I APPLICATION FILED MAY 12. 1920 1,380,317.

4 SHEEYS-SHEET 4- Ezyentar:

Oscar Gutaf90n I Q (OM (5] [4 /144 Avg/y.

vPatented May 31., 1921.

UNITED STATES PATENT OFFICE.

TOOL-HOLDER.

Specification of Letters Patent.

Patented May 31, 1921.

Application filed May 12, 1920. Serial No. 380,837.

T 0 all whom it may concern:

Be it known that 1, Oscar. GUs'rArsoN, a citizen of the United States,residing at Seattle, in the county of King and State of l/Vashingtonhave invented certain new and useful Improvements in Tool-Holders, ofwhich the following is a specification.

My invention relates to that class of tool holders employed in lathes,planers, screw machines, boring machines, etc.

One object of my invention is to provide a holder which will firmly gripthe cutter blade and hold it in the proper position and is adapted toreceive blades of different sizes. A further object is toprovide aholder which will hold the tool in its natural position with relation tothe work so that it will cut evenly without biting into the work orchattering, thus avoiding the danger of breaking the cutter or ofspoiling the work.

In the following description, I shall refer to the accompanying drawingsin which- Figures 1, 2 and 3 are side elevation, end elevation, and topplan views respectively of a straight tool holder embodying myinvention; Figs. 4- and 6 are side elevation and top plan viewsrespectively of a left-hand tool holder; Fig. 5 is a vertical sectionalview on the line 5-5 of Fig. 8; Fig. 7 is a longitudinal plan view ofthe clamping bolt; Fig. 8 is a fragmentary sideelevation of the clampingend of the tool upon the side opposite that shown in Fig. 1; Fig. 9 is atop plan view of a right hand holder; Fig. 10 is a vertical sectionalview on the line 10 -10 of Fig. 9; Figs. 11 and 12 are side elevationsofthe same taken from opposite sides; Fig. 13 is an end elevation of thesame; Fig. 1-1 is a fragmentary conventional view, partly in section ofa lathe showing my tool holder with a cutting tool in operativeposition, the lathe shaft rotating in opposite direction from the usual;Figs. 15 and 16 are top plan views respectively, of the tool holdersadapted for boring-mill machines rotating in the usual direction; Figs.17 and 18 are side and end elevations of the holder shown in Fig. 15;Figs. 19 and 20 are fragmentary conventional side elevations of avertical spindle boring mill machine showing my tool holder in operativeposition; Figs. 21

and 22 are top plan and end elevation of a tool holder which enables thecutting tool to tsnugly against the side of the tool shank, so that theholder and tool maybe received by the opening in the tool rest; Figs. 23and 21- are side elevations taken from opposite sides of the same; andFig. 25 is a fragmentary conventional end elevation of a turret latheand screw machine showing my tool holders in the front and rear toolposts.

Thetoolholder embodying my invention comprises an elongated shankportion 2 and an integral thickened head portion 3 to which the cuttingtool is secured. In the forms shown on Sheets 1 and 2 of the drawings,the head is provided with an offset portion so that the tool holdinggroove 1 may be mainly at one side of the shank. The

purpose of this is to enable the cutting edge ofthe cutter to be placedon the diameter of the work with the tool and the shank uponoppositesides thereof. This is illustrated in F 14 which shows the shank2 clamped in the tool post 7 below the horizontal diameter of the work 8which is clamped in the lathe stack 9. while the cutting tool 10 islocated above the horizontal diameter of the work.

The advantage of this arrangement will be appreciated by machinists andthose who have had experience in lathe work. The cutting edge of thetool bears directly upon the horizontal diameter of the work so thatthere is no tendency of the tool to bite into. the work and thisarrangement also obviates any tendency of thetool to chatter. I amtherefore able to obtain asmooth, even cut and without danger ofbreaking the tool or of injuring the work on the chuck.

The blade tapers from the cutting edge to the rear edge. The lowerflange 48 of the notch in the head upon which the cutting side of thetool bears is supportedby a heavy rearwardly and downwardly through thehead and passing through the lower side of the holder adjacent the rearedge. The lower side of the head 3 is beveled rearwardly so that it isperpendicular to the axis of the bolt. In order that the bolt mayoverhang the tool in the plane thereof,'the bolt hole extends throughthe front wall at the upper flange 4% and the enlarged head'15 isbeveled or flattened at 15 so that it will lie in the plane of the toolface of the holder. The

' turretlathes and screw machines.

1 extend alongside of the shank.

bore of the bolt hole is enlarged at the upper end to conform to thesize of the head of the bolt while the lower portion of the boreconforms to the size of the shank of the bolt. This is the advantage ofleaving as much metal as possible in the main body of the head whichreceives the thrust and strains of the cutter.

The notch 15 which is cut into the. inner end of the enlarged head ofthe bolt slants inwardly from the base at such an angle that the face ofthe notch will be substantially parallel with the axis of the toolholder head when the bolt is in position. The incline of the bolt causesthe upper edge of the notch 15 to slant slightly downwardly over thetool thereby forcing the tool rearwardly' against the side face of thenotch as the bolt is tightened by means of the nut 16 so that the cutteris securely held in a vise-like grip between the head of the bolt andthe flange 41 of the holder. In order to prevent any tendency to axialmovement of the bolt, a notch 17 is cut in the rear side'of the bolthead and receives a pin 18 secured in the head.

The advantage of the clamping device above described will now beappreciated by engineers and machinists. It will be evident that thethrusts and strains transmitted through the cutter are received by theclamp ing bolt in a direction longitudinal of its axis so that there isno shearing strain produced upon the bolt and the grip upon the tool maybe made as tight as desired. By reason of the oblique position of thebolt the tool is drawn tightly in a lateral direction against the boltby the same action which draws it downwardlyagainst the flange 1 of thehead. t will also be observed that by reason of the inclined position ofthe bolt, there is a small component of the thrust from the cutter bladewhich is transverse to the bolt head and this has a tendency to maintainthe cutter blade tight against the side face of the notch in the bolt.All of these forces, therefore, act in a direction to maintain the bladefirmly in the head without any tendency to move away from the side faceof the notch 4 against which the blade is drawn when the bolt istightened.

In Sheets 3 and 4 of the drawings I have shown aform of holder in whichthe face of the head which carries the cutting tool is substantially inalinement with the shank but is offset laterally a distance suflicientto permit the rear end of the cutter blade to This makes a very'compactconstruction which is especially adapted for use with boring millmachines, as illustrated conventionally in Figs. 19 and 20. It isalsoadapted for universal By offsetting the head laterally the tool canoperate up to a face or offset of the work. Thus in Fig. 19 the cutteris operating along the vertical face of the work which is being rotatedon a vertical axis in the machine and the tool can operate down to thehorizontal offset or face 8 of the work; and in Fig. 20 the tooloperating back and forth across the horizontal face 8 of the work, canoperate close to the vertical face of the work. The advantage f thisoffset construction of the holder head will be appreciated bymachinists.

In Fig. 25 I have shown cutters operating upon opposite sides of thework, both cutting upon the horizontal diameter thereof, the tool andholder in the rear post 7 being reversed in position from that in thefront post 7, these posts being supported in a compound rest 21.

In the accompanying drawings I have illustrated a number of differentforms of my holder for the purpose of clearly disclosing embodiments ofmy invention, but it will be evident to engineers that various otherforms and modifications may be made without departing in any manner fromthe invention. My clamping device is not only as simple in constructionas is possible, but requires no auxiliary members. Cutting blades ofdifferent sizes may be employed and each will be held with the same firmvise-like grip between the shoulder 15 of the bolt and the flange 4" ofthe head and will be drawn firmly against the rear face of the slot f byreason of the inclination of the bolt in the head. As previously pointedout, when the bolt is tightened by means of the nut 16 pressure issimultaneously brought upon the cutting blade to press it firmly againstthe ledge or flange 4 and to move it laterally'against the rear face ofthe notch 4 in the head. At the same time the blade is properlypositioned in the holder for the cutting operation.

Having now described my invention what I claim as new and desire toprotect by Letters Patent is 1. A tool holder for the cutters of lathes,boring mill machines, planers, etc., comprising integral shank and headportions, the latter being provided with a groove in its side faceextending longitudinally thereof for the reception of a cutter, a boltextending through a passage in said head and projecting through the facethereof at the top of said groove and extending rearwardly anddownwardly oblique to the sides of the head, a notch in the head of thebolt providing an overhanging flange to engage one edge of the cutterand clamp it against the opposite ledge of said groove.

2. A tool holder for the cutters of lathes, boring mill machines,planers, etc., comprising integral shank and headportions, the latterbeing provided with a groove in its side face extending longitudinallythereof for the reception of a cutter, a bolt extending through the headfrom top to bottom thereof oblique to the plane of said groove said bolthaving a notch to receive one edge of the cutter and clamping theopposite edge against the opposite ledge of the groove.

3. A tool holder for the cutters of lathes, boring mill machines,planers, etc., comprising an integral shank and clamping head,

the latter being provided with a laterally extending ledge, a boltextending obliquely through the head and provided with a flange 0roifset which overhangs said ledge, where- 15 cutter will be drawninwardly against the 20 side face of the head.

In testimony whereof I afiix my signature.

OSCAR eUsTAFsoN;

